A blood circuit for medical application includes a blood circuit used for, for example, a dialysis. The dialysis requires not only a dialyzer but also a blood circuit for connecting a patient to the dialyzer. Conventionally, this blood circuit for dialysis varies in specifications depending upon users, i.e., hospitals, doctors, or laboratory technicians. That is, most of the conventional blood circuits are customized for individual users and do not have general versatility. Actually, a large number of different kinds of blood circuit systems are employed.
Since such blood circuits are customized for individual users, the cost is high and it takes a long time to deliver the products to users. In other words, it takes a long time to configure a circuit by repeating trials and errors, which may lead to increased cost. A more important problem is that a dialysis technique is dependent on the experience of in the individual person in charge such as a doctor, a laboratory technician, etc., and a method of connecting each machine to the circuit system and a method of using the circuit system are not systematized. Therefore, a circuit system may be changed subjectively by the individual person in charge. Furthermore, compatibility between different products is not established. Thus, there are problems in safety as a product used directly on the human body. Examples of such problems are a safety problem, for example, failure in fitting of a tool such as an indwelling needle, etc. that is connected to the circuit, and a lack of versatility, that is, because of a difference in length even on the order of only several centimeters, such an apparatus has to be produced based on a different standard.
On the other hand, with the stability of the performance of dialyzers in recent years, the safety of blood circuits, ease of using, and economical efficiency are becoming problems. In order to solve such problems, it is urgently demanded to standardize various components constituting a blood circuit and to provide the stability in quality, convenience, and rapidity in configuring a circuit.
With respect to the demand, JP63 (1988)-95063A proposes that each component is integrated into one piece of a packaged system. However, this proposal has disadvantages in that equipment being connected to the circuit system has less versatility, and that the system is not used conveniently.
Furthermore, there are about 3400 types of blood circuits only in Japan. Conventionally, problems with respect to the conveniences in using, for example, length, location of parts, etc., are adjusted by trial and error and samples are made and attached to a dialyzer. In other words, the adjustments have been carried out by using a real machine.
In order to make samples, it is necessary to make a standard drawing and often calculate the amount of filled blood or length based on the standard drawing. If defects are detected in the test by the use of real machines, there is a bother to start again from the formation of standard drawings.